on the Regulatory Treatment of Styrene
Styrene monomer is very well monitored and regulated throughout the world, as are the products made from styrene and the processes by which those products are manufactured. This section contains basic information on regulations pertaining to styrene around the world.
The use of styrene monomer and styrene based plastics in Europe is impacted by both European Union (EU) regulations and directives, as well as by national (individual country) regulatory processes.
EU Risk Assessment Review
Styrene monomer is one of many large volume chemicals subject to review based on the European regulation EEC/793/93, which requires chemical risk assessments. This process evaluates both the hazard (e.g. potential for causing health effects) of a substance and the real-life potential for exposure to that substance (e.g. in the environment, workplace, etc.) to determine whether or not there might be a risk from exposure to a substance under certain conditions. The United Kingdom's (UK) Health and Safety Executive (HSE) has drafted this risk assessment, which is due to be reviewed by EU experts during December 2001, and will be the basis for reviewing the classification of the product, its labelling requirements, and also regulations concerned with worker exposure.
Based on the current EU classifications, styrene monomer is considered to have low oral toxicity, and is not classified in terms of carcinogenicity or mutagenicity. However in common with many organic solvents, there are regulations setting inhalation exposure limits for people working with styrene monomer. Current occupational exposure regulations, in parts per million (ppm), are:
Detailed information on handling the product is contained in Safety Data Sheets (SDS), which describe potential health or safety factors.
Food Contact Regulations
Food contact legislation for all plastics within the EU, including styrenic plastics, is based on a system of self-certification. The plastic resin producers have a duty to ensure that the products they market for food contact uses comply with applicable regulations, and also to certify this fact to their customers.
In order to safeguard the quality of the food being packaged, there are limits that govern the maximum allowable amounts of additives and volatile components that are allowed to migrate into the foodstuff. In the case of styrene-based plastics, there is not a Specific Migration Limit (SML) for the monomer, however for the final article, the overall migration must not exceed 10 mg/dm².
In addition to the above regulations, the taste of the food being packaged
should not be negatively impacted by the plastic package, and the manner
in which the package is made should comply with good manufacturing practices.